This invention relates generally to automated irrigation systems and, more particularly, to systems for the control of irrigation devices, such as valves, pumps and rotors. Water valves and pumps are used to control the flow of irrigation water through a variety of water dispensing devices, including rotors. Rotors irrigate by throwing a jet or spray of water that is rotated about a generally vertical axis. Rotors are typically enclosed in a protective housing, and a rotating nozzle pops up from the top of the housing during desired irrigation times. Rotors are supplied with water from water supply lines that are usually installed below ground and are typically actuated by electric solenoid-controlled valves. Rotation of the nozzle may be effected by a self-contained water turbine and a reduction gear mechanism, or the nozzle may be of the impact-arm type, which utilizes the angular momentum of a spring-loaded oscillating arm to rotate the nozzle in small angular increments through a desired arc, or continuously through a full circle of rotation.
Valves, pumps and rotors are used in a wide variety of irrigation applications, from residential and commercial landscapes to golf course and agricultural irrigation. The application to golf course irrigation is mentioned here by way of example, but as the description of the invention proceeds it will be understood that the principles described are equally applicable to other types irrigation environments. A common feature of underground irrigation systems is that control wires must be run from a controller to each solenoid valve and pump that controls the flow of water to a sprinkler or group of sprinklers. Control wires to the valves, pumps and rotors are typically buried below ground, often in the same trenches used to run supply pipes to the valves. Control systems vary from simple multi-station timers to complex computer-based controllers.
The advantages of a wireless rotor, using a battery to control the solenoid valve, have been recognized by others. For example, U.S. Pat. No. 4,626,984 to Unruh, U.S. Pat. No. 5,813,655 to Pinchott et al., and U.S. Pat. No. 4,962,522 to Marian, broadly suggest some features of a wireless rotor. None of these patents, however, suggest all of the features of the present invention, which are summarized below.
The present invention resides in a wireless irrigation control device. Briefly, and in general terms, the wireless irrigation control device of the invention comprises a water control device, which may be a rotor, a valve or a pump, and a controller coupled to the water flow control device. The controller includes a housing, an antenna integrated into the housing and capable of receiving radio-frequency (RF) signals, a microcontroller contained within the housing and coupled to receive and process signals from the antenna, and a memory module for storing watering schedules established or modified by signals received through the antenna. The wireless irrigation control device also includes a battery power supply also contained within the housing, to supply power to the microcontroller and to the water control device. Preferably, the wireless irrigation control device further comprises a battery charge generator integrated into the controller housing and coupled to the battery power supply. The battery charge generator may be a solar panel, a water turbine or any other device for recharging the battery power supply.
Another aspect of the invention includes a magnetic proximity switch installed in the controller housing and coupled to the microcontroller. The magnetic proximity switch is configured to perform a function such as resetting the microcontroller, initiating a desired irrigation program sequence, or initiating a secured irrigation program sequence to allow system initialization.
Preferably, the controller has RF reception capability to process both short-range signals transmitted from a location near the irrigation control device and longer-range signals transmitted through a public broadcast system. The controller may receive short-range and longer-range RF signals through separate receivers operating in parallel at different frequencies, or may receive short-range and longer-range RF signals through a single receiver employing time-division multiplexing.
In accordance with another aspect of the invention, the microcontroller includes means for processing received signals indicative of real-time control commands directed to the water flow control device. These control commands may be signals for scheduling ON and OFF times for the water flow control device, or for setting a real-time clock based on the received signals, such as for making an adjustment for latency of transmission through a public broadcasting system. The means for processing received signals may also include means for adjusting irrigation control commands and sequences for the water flow control device.
In accordance with another aspect of the invention, the wireless irrigation control device further includes a visual status indicator coupled to the controller and integrated into the housing. The visual status indicator is indicative of conditions such as battery condition, receipt of a control signal by the antenna, or fault conditions detected in the controller.
The present invention may also be defined in terms of a method for controlling a wireless irrigation control device contained in a controller housing. Briefly, the method comprises the steps of receiving broadcast signals through an antenna installed in the housing; decoding the received broadcast signals and confirming that they apply to this particular irrigation control device; based on data received through the antenna from time to time, and decoded in the preceding step, storing and updating at least one watering schedule in a memory module; and based on the stored watering schedule, generating signals to control a water control device in accordance with the watering schedule. The step of generating signals to control a water control device may be directed to any suitable device, such as a rotor, a valve or a pump.
The method of the invention may further comprise recharging, as needed, a battery housed in the rotor body, using a battery charging generator integrated into the rotor body. The method of the invention may further comprise the step of configuring the controller by transmitting signals to it through a magnetic proximity switch, or configuring the controller by transmitting signals to it from a handheld transmitter.
The method of the invention may further include the step of verifying that command signals have been transmitted to the wireless irrigation control device by receiving the same signals in a verification receiver. After verifying transmission, the method may further include the steps of determining a transmission latency time from the verifying step, and transmitting a clock adjustment signal to the wireless irrigation control device, to compensate for the determined latency time.
The method of the invention may further comprise the step of displaying a condition of the controller in a display device associated with the controller. The displaying step may include displaying battery condition, displaying receiver status, or displaying a controller fault condition.
It will be appreciated from the foregoing summary that the present invention represents a significant advance in the field of irrigation control devices. In particular, the invention provides an irrigation control device that requires no outside electrical connections but is still controllable from a remote location. Because the controller, power supply, antenna and recharging generator are all integrated into a conventional rotor body or other housing, the invention may be readily implemented in new irrigation systems or retrofitted in existing ones that were originally hard-wired to a central controller. Other aspects and advantages of the invention will become apparent from the following more detailed description, taken in conjunction with the accompanying drawings.